In 1969 a landmark scientific paper in the water-from-air field appeared in the Journal of Hydrology. The paper, authored by the Swedish researcher B. Hellström was titled "Potable water extracted from the air report on laboratory experiments". It is available for purchase from Elsevier B.V. It remains a scientifically informative and inspiring read for those of us fascinated by the potential for using water-from-air technology to improve water security in water-scarce regions.

Hellström, who was Professor of Hydraulics at the Royal Institute of Technology, Stockholm, performed water-from-air experiments with a dehumidifier machine at the Institute during July and August 1957. Earlier, in 1953 he had done non-mechanical dew collection experiments at the Institute.

Does using water-from-air technology in Brazil make sense? After all, the country contains about 20% of Earth's fresh water resources. But, there are problems in distributing drinking water to the entire population of Brazil. This paragraph from the Wikipedia article, Water supply and sanitation in Brazil reveals the reality, particularly for people in rural regions:

Access to piped water supply in Brazil stood at 77% and access to improved sanitation also at 77% in 2006.[1][7] Coverage is significantly higher in urban areas, where 84% of the Brazilian population live. Urban coverage is 96% for water and 83% for improved sanitation, including 53% access to sewerage, the remainder being accounted for by on-site sanitation. Coverage in rural areas, where 16% of Brazil’s population lives, is much lower. It stands at 57% for improved water supply and only 37% for improved sanitation. Geographically coverage is lowest in the country’s poorest regions: particularly in predominantly rural North, Northeast, and Center-West.

Filling the gaps in drinking water distribution infrastructure, with atmospheric water vapour processors (atmospheric water generators) can be a useful alternative. The water-from-air resource is plentiful in much of Brazil as shown by the Water-from-Air Resource (WFAR) annual indices for nine Brazilian sites tabulated here:

When the water-from-air resource monthly index = 1.00, the expected drinking water production rate from a atmospheric water generator (AWG) at the site should be the same as the machine's specified water-from-air production rate. Water-from-Air Resource annual index grades: Excellent: Index is greater than or equal to 1.00 Good: Index range 0.76 to 0.99 Fair: Index range 0.51 to 0.75 Poor: Index range is less than or equal to 0.50

World Environmental Solutions Pty Limited of Australia has developed a natural gas powered system called MultiGen which does the following:- produces water from air- heats and air conditions buildings- generates electricity

A press release today said a system to be installed at an Australian Government Education Institution in the Riverina district of New South Wales has a water-from-air capacity of 450,000 L per year (1232 L per day). The water will be used for landscape irrigation.

This is an example of water-from-air technology maturing and moving into the mainstream of water supply solutions.

I recently discovered an interesting web site about the Sanakvo Foundation's water-from-air project. The Sanakvo process is passive, needing no mechanical or electrical energy input. It consists of two steps:

Absorption of water vapour into a glycerol solution

Solar distillation to recover liquid water from the glycerol solution

The Sanakvo Foundation or Stiftung Sanakvo is a Swiss, non-profit, humanitarian foundation. Their goal is to develop and supply the Sanakvo process to people in regions suffering from clean water scarcity. The website explained that, "Sanakvo" means "healthy water" in Esperanto. Please visit the Sanakvo site following their link on my Project Links page.